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Abstract

Background

To characterize ease in discussing death (EID) and its influence on health valuation
in a multi-ethnic Asian population and to determine the acceptability of various descriptors
of death and "pits"/"all-worst" in health valuation.

Methods

In-depth interviews (English or mother-tongue) among adult Chinese, Malay and Indian
Singaporeans selected to represent both genders and a wide range of ages/educational
levels. Subjects rated using 0–10 visual analogue scales (VAS): (1) EID, (2) acceptability
of 8 descriptors for death, and (3) appropriateness of "pits" and "all-worst" as descriptors
for the worst possible health state. Subjects also valued 3 health states using VAS
followed by time trade-off (TTO). The influence of sociocultural variables on EID
and these descriptors was studied using univariable analyses and multiple linear regression
(MLR). The influence of EID on VAS/TTO utilities with adjustment for sociocultural
variables was assessed using MLR.

Conclusion

Singaporeans were generally comfortable with discussing death and had clear preferences
for several descriptors of death and for "all-worst". EID is unlikely to influence
health preference measurement in health valuation studies.

Background

Health valuation studies are performed to understand population preferences for various
health states and are important in informing healthcare resource allocation [1]. The topic of death is invariably raised in such studies as subjects are required
to value death either directly, for example, when visual analogue scales (VAS) are
used or indirectly, for example, when time trade-off (TTO) or standard gamble (SG)
are used [2]. Previous studies have found that health preferences may be influenced by respondent
characteristics such as age [3], social class [4], educational status [4] and presence of illness [5,6]. However, to the best of our knowledge, no studies have investigated how willingness
to discuss death may affect health preference measurements in health valuation studies.

Reluctance to discuss death may potentially reduce participation in health valuation
studies, thus resulting in selection bias. It may also increase the prevalence of
missing valuation data for the health state of being dead, which is particularly problematic
because these values are required to rescale raw scores onto a 0 (dead) to 1 (perfect
health) scale [7]. These missing values would also render other associated data unusable, resulting
in significant data wastage [8]. Reported prevalence of missing dead valuations ranged from 8% to 71% [8-10]. Reluctance to discuss death may be particularly relevant in an Asian population,
where, for example, many Japanese and Chinese avoid talking about death because they
believe that doing so may bring misfortune [11-13].

Differences in Asian and non-Asian views about death and dying could potentially influence
health preference measurements in several ways. First, in general, Asians may view
death and other health-related decisions as family rather than personal matters, in
contrast to Caucasians who may value individualism and autonomy [14]. As such, Asians are more likely to value health by taking their families' needs
into consideration. Second, Asians, notably the Japanese, generally prefer not to
be a burden to others [15]. Hence, they are more likely than Caucasians to assign higher values for the health
state of being dead and lower values to those health states in which they are dependent
on others (e.g. confined to bed) [16]. By highlighting these cultural differences, we are not implying that views on death
are clearly demarcated between Asians and Caucasians. Rather, these important cultural
differences suggest that health preferences generated from Caucasian populations may
not fully reflect health preferences among Asians and therefore may not be suitable
for use in healthcare decision making in Asia. An understanding of the Asian perception
towards death is also necessary for handling and interpreting logically inconsistent
values in health preferences [17], because the logical order of health states (from worst to best) may be different
in different cultures. An understanding of terms used to describe the worst possible
health state is also germane in this context, in particular as the term "pits", which
has been used in health preference studies, is a British colloquial term which may
not be well-understood in this Asian population.

The aims of this study were thus to characterize ease in discussing death (EID) and
its influence on health preference measurement and to determine the acceptability
of various descriptors of death and "pits"/"all-worst" in health valuation in a multi-ethnic
Asian population. We characterised EID and its influence on health preference measurement
by evaluating subjects' EID and explored the influence of sociocultural variables
on EID. We also studied the influence of EID on VAS/TTO utilities with and without
adjustments for sociocultural variables, as this could impact on health preferences
and might therefore need to be adjusted for in health valuation studies. We determined
the acceptability of various descriptors of death and "pits"/"all-worst" in health
valuation and explored the influence of sociocultural variables on the acceptability
of these descriptors (of death, pits and all-worst). We studied the appropriateness
of these commonly used descriptors because they represent alternative lower anchors
for the continuum of health in health valuation studies, with perfect health representing
the upper anchor. Hence, the choice of words to describe these health states could
potentially influence health preference measurements.

Methods

Subjects

In this Institutional Review Board approved study, in-depth interviews in either English
or the subject's mother-tongue (i.e. Chinese, Malay or Tamil) by interviewers of the
same ethnic group were conducted among consenting Chinese, Malay and Indian Singaporeans
(distribution in the general population: 78% Chinese, 14% Malay, 7% Indians; % English-speaking
only: Chinese – 16%, Malays – 2%, Indians: 22%; % Bilinguals: Chinese – 32%, Malays:
20%, Indians: 55%) with at least 6 years of education. The various mother-tongue versions
of the questionnaire were translated based on the English version. To achieve adequate
representation, 2 male subjects (one speaking English, the other his respective mother
tongue) and 2 female subjects (one speaking English, the other her respective mother
tongue) from each age band (20–29, 30–39, 40–49, 50–59, >60) were recruited from the
general population, giving a minimum of 20 subjects per ethnic group.

Study design

This study was conducted in 3 stages. First, subjects were asked to comment on and
rate, using a 0 to 10 horizontal VAS, (1) EID (VAS anchors: most comfortable vs. least
comfortable) and (2) self-reported religiosity (a potential determinant of EID; measured
in response to the question, "On a scale of 0 to 10, how religious do you feel yourself
to be?").

Second, subjects were asked about their views regarding death, several descriptors
of death and "pits"/"all-worst". To facilitate the discussion, interviewers prompted
subjects with questions such as "How comfortable are you with discussing death?",
"Do you think it is a taboo to discuss death?", "Do you believe in life after death?".
Subjects' comments were recorded verbatim. Subjects were also asked to comment on
and rate, using a 0 to 10 horizontal VAS, (1) acceptability of eight commonly used
descriptors of death, i.e. "dead", "passed away", "death", "deceased", "demised",
"departed", "sudden death" and "immediate death" (VAS anchors: most acceptable vs.
least acceptable) and (2) appropriateness of "pits" and "all-worst" (VAS anchors:
most appropriate vs. least appropriate) in describing the worst possible health state
(the descriptors were shown on two separate cards).

Third, subjects completed a simple health valuation exercise to determine their preferences
for 3 hypothetical EQ-5D defined health states using a 0 to 10 vertical VAS (anchors:
best imaginable health state vs. worst imaginable health state) followed by the TTO
method. Each health state on the EQ-5D consists of one of 3 possible levels from each
of 5 single-item health dimensions. Perfect health on the EQ-5D would be described
as 11111 while the worst possible EQ-5D health state would be described as 33333.
The 3 health states used in this study were selected from those used in the EQ-5D
MVH protocol [18] representing mild (11122), moderate (23321) and severe (32313) impairments. Sociodemographic
information was collected using a standardised form. Self-report of chronic medical
conditions was determined using a list including diabetes mellitus, hypertension,
heart diseases, stroke, asthma or other lung diseases, cancer, rheumatism, back pain
or other bone or muscle illness, and mental illness (including depression, anxiety
neurosis, schizophrenia).

Data and statistical analyses

Subjects' characteristics were compared using Fisher's exact or Chi-squared tests
for categorical variables or Kruskal-Wallis test for continuous variables, where appropriate.
Key points from verbatim records of subjects' comments on (1) EID, (2) acceptability
of descriptors of death and (3) appropriateness of "pits" and "all-worst" were summarised.

To study the influence of sociocultural variables including sociodemographic and clinical
variables and self-reported religiosity on (1) EID, (2) acceptability of descriptors
of death and (3) appropriateness of "pits" and "all-worst", we assessed the relationships
between these variables in univariable analyses using Mann-Whitney or Kruskal-Wallis
tests (categorical independent variables) or Spearman's correlation (continuous independent
variables). Independent variables with p < 0.10 in univariable analyses were then
entered into the multiple linear regression (MLR) models. Due to the small number
of subjects, we considered the results of MLR analysis exploratory.

To determine the influence of EID on VAS/TTO utilities without adjustment for sociocultural
variables for each health state, we assessed the relationships between these variables
using Spearman's rank correlation. To determine the influence of EID on VAS/TTO utilities
with adjustment for sociocultural variables, we planned MLR in two steps. First, separate
preliminary MLR models with EID and a single sociocultural variable as independent
variables were created for each health state. Hence, for each health state, a total
of eight models were generated, one for each sociocultural variable investigated.
Second, a final MLR model with EID and multiple sociocultural variables were created
for each health state. Only those sociocultural variables with p < 0.10 from the preliminary
models were included in this final model. Data were analysed with STATA [19].

Results

Response rate and subject characteristics

Of 69 subjects approached, 63 (91%) participated, two declined participation because
they were busy and four declined after hearing that the survey was a discussion on
death. None of the subjects terminated the survey prematurely, although they had been
informed that they had the freedom to do so. Distribution of subject characteristics
and responses are given in Table 1. By design, there was approximately equal number of subjects from each ethnic group,
and from both genders. As compared to Malay and Indian subjects, Chinese subjects
reported more years of education (p = 0.019). Overall religiosity was moderate (median
religiosity scores (IQR): 6.0 (5.0, 8.0)). As compared to Malay and Indian subjects,
Chinese subjects reported lower religiosity (median religiosity scores (IQR): 5.0
(2.3, 7.0) vs. 6.5 (5.0, 8.8) vs. 7.0 (5.0, 10), p = 0.036).

Table 1. Subject Characteristics and Distribution of Responses by Ethnicity

Influence of ease in discussing death on health utilities without and with adjustment
for sociocultural variables

Correlations between EID and health utilities for the 3 assessed health states were
generally weak for all subjects (range: VAS: -0.23 to 0.07; TTO: -0.14 to 0.11, Table
3) and among individual ethnic groups, with the exception of Malay subjects in whom
EID showed a moderate correlation with the moderately impaired health state measured
using VAS (but not TTO).

Table 3. Correlation between Ease in Discussing Death and Health Utilities

In the preliminary MLR models including a single sociocultural variable, ethnicity
was the only sociocultural variable with p < 0.10 for the moderately impaired health
state measured using VAS (Table 4). Hence, the final MLR model was not generated.

Table 4. Analyses of the Influence of Ease in Discussing Death (EID) and a Single Sociocultural
Variable on VAS Scores in Separate Multiple Linear Regression Models for Moderately
Impaired Health State (23321)

Discussion on death and acceptability of descriptors of death

Subjects' responses to standardised questions regarding death were as follows:

(A) Comfort level in describing death

Over half of our subjects (32/63) felt comfortable with discussing death, verbalizing
that death is "natural", "it happens to everyone" or "once you are born, you have
to die", etc. One 81-year old Chinese female said that discussing death was not problematic
because she was already very old. Another 30-year old Chinese male was comfortable
discussing death because "death seemed to be quite far away from me". Five (8%) subjects
specified that they were not comfortable discussing death. Among them, one 56-year
old Chinese female said that she would be uncomfortable discussing death if this were
not a survey. One 62-year old Malay male felt that death cannot be discussed, and
another 45-year old Malay male said that he was uncomfortable discussing death because
he wanted to live longer.

(B) Taboo to discuss death

Only one Chinese (5%) and two Malay subjects (10%) felt it was a taboo to discuss
death.

(C) Fear of death

All except 5 (25%) Malay subjects (3 males and 2 females) said they did not fear death.
These five subjects did not explain why they feared death.

(D) Belief in life after death

Interestingly, many subjects (31/63) said they believed in life after death. Two Indian
and three Malay subjects said that their religious beliefs influenced their views
on death. For four of these subjects, self-reported religiosity was high (range 7
to 10). The fifth subject gave a religiosity score of 5.0.

Although most subjects were comfortable with discussing death, they felt some descriptors
of death were more acceptable than others (Table 1). In general, "passed away", "departed" and "deceased" were the most well-accepted
descriptors while "sudden death" and "immediate death" were the least well-accepted.
Ethnic differences in acceptability of "sudden death" (p = 0.035) and "immediate death"
(p = 0.033) were observed, with Indian subjects finding these descriptors less acceptable
than Chinese or Malay subjects.

In univariable analyses, one or more sociocultural variables influenced acceptability
of six descriptors of death (p < 0.10, Table 5) except "passed away" and "death". However, in multivariable analyses only the presence
of chronic medical condition remained significantly associated with acceptability
of "departed" (regression coefficient (95% confidence interval, CI): -1.3 (-2.6, -0.053),
p = 0.042).

Table 5. Univariable Analyses of the Influence of Sociocultural Variables on Descriptors of
Death.

Pits versus all-worst

The majority of subjects (n = 42, 64%) felt that "all-worst" was a better description
than "pits" for the worst possible health state on all EQ-5D dimensions (p < 0.001,
Table 1). This preference was also reflected in the higher appropriateness scores for "all-worst"
versus "pits" (median appropriateness scores (IQR): 7.0 (5.0, 9.0) vs. 4.0 (0, 8.0),
p < 0.001). Among subjects who preferred "all-worst", six said they did not know the
meaning of "pits". One Malay male said that "pits" sounded like pig and would be offensive.
Five Malay subjects (all completing the interviews in Malay) thought "pits" meant
graveyard. This suggested that the translation was problematic. However, bilingual
subjects in this study were of the opinion that there was no better Malay translation
for "pits". Although Malay subjects preferred "all-worst" to "pits", they did not
think "all-worst" was very appropriate and suggested using "most terrible" (8/20)
instead. Other suggested descriptions for the worst possible health states by all
subjects included "most undesirable" (18/63), "most terrible" (13/63) or "worst" (6/63).

Table 6. Univariable Analyses of the Influence of Sociocultural Variables on "Pits" and "All-Worst".

Discussion

In this study among Chinese, Malay and Indian subjects living in Singapore, a multi-ethnic
Asian urban state, we characterised ease in discussing death and its influence on
health valuation in a multi-ethnic Asian population and determined the acceptability
of various descriptors of death and "pits"/"all-worst" in health valuation. We found
that subjects were generally comfortable with discussing death. Correlations between
EID and VAS/TTO utilities were generally weak, suggesting that EID was unlikely to
influence health preference measurement in health valuation studies. We also found
that among eight descriptors of death, "passed away", "departed" and "deceased" were
the most well-accepted and "sudden death" and "immediate death" were the least well-accepted.
The majority of subjects felt that "all-worst" was a better description than "pits"
for the worst possible health state.

Our findings are important in several ways. First, to the best of our knowledge, this
is the first study to evaluate EID and its influence on health valuation. Our findings
suggest that EID is unlikely to affect participation rate (since very few subjects
declined participation and none terminated the study prematurely) and cross-cultural
comparability of, or to introduce response biases due to unwillingness to discuss
death in health valuation studies in Singapore. They also provide a basis and baseline
for comparison with similar studies in other socio-cultural contexts.

Second, our finding that sociocultural variables influenced acceptability of several
descriptors of death and subjects' assessment of appropriateness of "all-worst" is
important in helping to identify the preferred descriptors for use in health valuation
studies. For example, the ideal descriptor of death should be one that is not influenced
by any of these sociocultural variables. Descriptors that would satisfy this criterion
include "passed away" and "death".

Third, to the best of our knowledge, this is the first study that evaluated cultural
differences in EID in a semi-quantitative manner. By asking subjects to rate their
EID and acceptability of various descriptors, we were able to identify factors that
predict acceptability of these descriptors, thus allowing better designed health valuation
studies. Fourth, being the first of such studies in Asia, this study also provides
useful empirical data to inform design of future valuation studies in an Asian context.

Several aspects of our findings deserve mention. First, the relatively low acceptability
of "immediate death" raises a concern about cross-cultural comparability of health
valuation studies using this term, which has been commonly used as a descriptor in
previous health valuation studies. Due to its relatively low acceptability in this
Asian population, subjects may feel offended and be less willing to participate in
or complete such studies. Hence, it might be advisable to replace "immediate death"
with other descriptors that were better accepted. Ethnic differences in acceptance
of "immediate death" may also introduce a systematic bias. For example, participation
rates may be lower, rates of missing data may be higher and preference scores for
that health state may be lower among Indian subjects compared to Chinese or Malay
subjects. An alternative interpretation of this data is that the low acceptability
of "immediate death" suggests that it is an appropriate descriptor for a health state
that is to be avoided at all costs. Thus, further studies are required to investigate
the impact on measurement of health preferences if an alternative to "immediate death"
is used as descriptor in health valuation studies.

Second, we recognize that some descriptors of death may be more suitable in a given
situation. For example, sudden death would be an appropriate descriptor in studies
involving patients with acute myocardial infarction. However, ethnic differences in
acceptability of sudden death may introduce bias, and for this reason it would be
more appropriate to use an alternative descriptor, which would not introduce this
potential bias, even it is if less medically accurate.

Third, the strong preference for "all-worst" over "pits" provides empirical evidence
for using this descriptor in future health valuation studies to be performed in this
population. Furthermore, as there is no appropriate translation for "pits" in the
Malay language, the use of "pits" should ideally be avoided in such studies. We found
interesting data suggesting important ethnic differences in the acceptability of descriptors
of death and "all-worst". The reasons for this are not clear, and could be related
to cultural differences in perception of the worst possible health state. This could
be studied in greater detail in future studies. Nevertheless, it was fairly clear
that "pits", a British colloquial term, was poorly understood in this study population.

We recognize several limitations of this study. First, the findings may not be readily
generalised to the Singaporean general population. For example, subjects with fewer
than 6 years of education were not included in this study. Given that EID is associated
with years of education, further studies are needed to know if subjects with fewer
than 6 years of education are comfortable with discussing death. Nevertheless, it
is unclear if subjects with low literacy can participate in health-state valuation
studies. Previous studies found that successful (i.e. non-missing, logical) responses
tend to come from younger and/or better educated subjects [20,21].

Second, with regards to acceptability of descriptors of death, the discussion was
carried out in a somewhat artificial setting. We did not evaluate the acceptability
of these descriptors in the context of actual health valuation studies. As one subject
pointed out, she was comfortable with discussing death only because this was a survey.
Further studies are needed to evaluate if these descriptors of death remain acceptable
in the context of actual health valuation studies. Third, given the sample size of
our study, the MLR analyses were exploratory.

Conclusion

In conclusion, we found in this study that Singaporeans were generally comfortable
with discussing death and had clear preferences for several descriptors of death and
for "all-worst". EID is unlikely to influence health preference measurement in health
valuation studies, which suggests that such studies could be performed in Singapore
without concerns about the potential impact of EID on participation rate, accuracy
of responses and cross-cultural comparability.

Abbreviations

EID Ease in discussing death;

MLR multiple linear regression;

SG standard gamble;

TTO time trade-off;

VAS visual analogue scale

Competing interests

The author(s) declare that they have no competing interests.

Authors' contributions

JT conceived the study, and participated and provided oversight for its design and
coordination. HL Wee, YB Cheung and DM participated in the design and coordination
of the study and performed the statistical analysis. SC Li, F Xie, XH Zhang, N Luo
and KY Fong participated in the design of the study and its coordination. All authors
read and approved the final manuscript.

Acknowledgements

This study was funded by a programme grant (03/1/27/18/226) from the Biomedical Research
Council of Singapore.

References

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